if (answer != null) return answer;
Instance sol = eval.instance();
StringBuilder sb = new StringBuilder();
sb.append("---INSTANCE---\n" + "integers={");
boolean firstTuple = true;
for(IndexedEntry<TupleSet> e:sol.intTuples()) {
if (firstTuple) firstTuple=false; else sb.append(", ");
// No need to print e.index() since we've ensured the Int atom's String representation is always equal to ""+e.index()
Object atom = e.value().iterator().next().atom(0);
sb.append(atom2name(atom));
}